Incremental pattern control system for sewing machines

ABSTRACT

A sewing machine work shifting mechanism is disclosed having a work holding frame which is shiftable in response to an incremental pattern control system. A manually influenced shifting means for the work holding frame is provided in order to locate the work holding frame in a selected starting position to provide a basis of reference for the pattern dictated by the incremental pattern control system.

United States Patent Ross 1451 Dec. 19, 1972 [54] INCREMENTAL PATTERN CONTROL SYSTEM FOR SEWING MACHINES [72] lnventor: Roger J. Ross, Roselle, NJ.

[73] Assignee: The Singer Company, New York,

[22] Filed: Aug. 26, 1971 [21] Appl. No.: 175,111

[52] U.S. Cl ..112/77 [51] Int. Cl. .,..DOSb 3/24 [58] .Field of Search ...l l2/77, 70, 86, 90, 102, 158 B [56] 4 References Cited A UNITED STATES PATENTS 3,029,758 4/1962 Hurme et al..... ..l l2/l02 Fresard et al ..l l2/l02 Howard ..l 12/77 ,Primary Examiner-H. Hampton Hunter AttorneyMarshall J. Breen et al.

[57] ABSTRACT A- sewing machine work shifting mechanism is disclosed having a work holding frame which is shiftable in response to an incremental. pattern control system. A manually influenced shifting means for the work holding frame is provided in order to locate the work holding frame in a selected starting position to provide a basis of'reference for the pattern dictated by the incremental pattern control system.

6 Claims, 3 Drawing Figures INCREMENTAL PATTERN CONTROL SYSTEM FOR SEWING MACHINES BACKGROUND OF THE INVENTION Work shifting mechanisms are known, such as that disclosed in the US. Pat. No. 3,370,509, Feb. 27, 1968 each stitch is dictated not in an absolute sense withrespect to a common basis of reference, but rather with relation only to the preceding stitch, i.e., the pattern information dictates only the increment of change between successive stiches. An incremental pattern control system has an advantage in that patterns covering large, practically unlimited areas can be, stitched using pattern information carriers which can be very narrow because they need dictate only the difference between successive stitches and not informationas'to the total distance of each stitch from a common basis of reference.

Using prior known incremental pattern control type systems for sewing machines such as that disclosed in the US. Pat. No. 3,029,758, Apr. 17, 1962 ofHurme et al, however, problems will be encountered if exchange of pattern information carriers is required, because no provision is included for selecting a starting position for the work shifting frame.

BRIEF SUMMARY OF THE INVENTION It is an object of this invention to provide in an incremental type pattern control system for a sewing machine work shifting mechanism, an effective solution to the problem of correlating the pattern of stitch formation with a fixed basis of reference so that a variety of different incremental pattern information carriers may be substituted readily in the system. The object of this invention is attained by provision in an incremental pattern control system of a manually influenced means for shifting the work holding frame so that the appropriate starting position of the stitching may be obtained relatively to a fixed basis of reference. In this way, incremental pattern information carriers corresponding, for instance, to the letters of the alphabet may be substituted as in monogram sewing, or the like.

DESCRIPTION OF THE DRAWING In the accompanying drawing:

FIG. 1 is a front perspective view of a work shifting attachment for sewing machines embodying this invention and including a fragment of an incremental pattern information carrying tape in readiness for insertion into the attachment,

FIG. 2 is a rear perspective view of the attachment of FIG. 1, and

FIG. 3 is a quasi-diagrammatic plan view of the mechanism of the attachment of FIGS. 1 and 2 for shifting the work holding frame of the attachment in one direction.

Referring to the drawings, denotes a work shifting attachment for a conventional sewing machine by which decorative or ornamental patterns of stitches may be formed in response to pattern information carried on a punched tape 11.

The specific details of construction of the attachment 10 do not form a part of this invention; the invention may be applied to any type of work shifting mechanism whether built in or in the form of an attachment. It is important only that the work shifting mechanism must respond to an incremental pattern control system; that is, a system in which pattern information controls the relation of each stitch to the preceding stitch rather than to a common basis of reference to all of the stiches. The details of construction of the work shifting attachment 10, therefore, will be described only generally and to the extent that the embodiment therein-of the present invention may be clearly understood.

The attachment 10 includes a frame formed in a seat 21 whereby the attachment frame may be secured to a sewing machine, for instance, on a presser bar (not shown) in place of a conventional presser foot fast on a transverse rock shaft 22 in the attachment frame is an operating lever 23 which is bifurcated as at 24'to embrace an operating part of the sewing machine as, for instance, the conventional needle clamp on a reciprocating needle bar (not shown) to drive the attachment.

At one side the transverse rock shaft'22 carries a rock arm 25 to which is secured a link 26 pivotally connected to an arm 27 protruding from a pawl carrier 28 slidably constrained in the attachment frame. Four ratchet pawls 30, 31, 32 and 33 are pivoted on the pawl carrier 28 preferably on a common pivot screw 34 thereon. The pawls are arranged in pairs, two pawls 30 and 31 above the pawl carrier, and two pawls 32 and 33 therebeneath, each pair of pawls serving as will be described 'hereinbelow to impart work shifting movement in a different direction.

At the opposite side the transverse rock shaft 22 carries a rock arm 35 connected by a link 36 to a pawl carrier 37 slidably constrained in the attachment frame. The pawl carrier has one ratchet pawl 39 pivotally supported thereon for cooperation with a ratchet wheel 40 fast on a tape carrying drum 41 adapted to index the punched tape 11. The drum 41 is formed with evenly spaced pins 42 cooperable with sprocket holes 43 along each edge of a tape 1 l for indexing the tape around the drum. A sheet metal tape guide 44 is fitted around the drum to direct the tape to and from the drum periphery. The guide 44 is formed with slots 45 providing access to the tape ll for a tape sensing device which will be described below.

The attachment includes a work holding frame formed with an aperture 51 within which an ornamental array of stitches may be formed when the work holding frame is shifted during operation of the sewing machine. The work holding frame is carried by a feed bar 52 which is constrained to move in a guide slot 53 in a swinging frame 54 pivoted beneath the attachment frame.

Work shifting movements can thus be imparted to the work holding frame in two substantially perpendicular directions; in one direction by sliding the feed bar 52 along the guide slot 53 in the swinging frame and in the other direction by turning the frame 54. Illustrated in FIG. 3 is a mechanism for influencing the movement of the work holding frame in one direction by sliding the feed bar along the guide slot 53. A pivoted drive link 60 connects the feed bar 52 with-a crank pin 61 carried on a rotary actuator 62 journalled in the attachment frame. Formed on or attached to the rotary actuator 62 is a gear 63 which is in mesh with a pinion 64 fast on the ratchet wheel 65 with which the pawl 30 cooperates. The gear 63 is also in mesh with an idler pinion 66 meshing with a pinion 67' fast on a ratchet wheel 68 with which the pawl 31 cooperates. Since the pawls 30 and 31 areboth pivotally carried on the pawl carrier 28, they can by selectively engaging the respective ratchet wheels 65 and 68 control movement of the feed bar 52 and thus motion of the work holding frame 50 back and forth in the direction of the guide slot 63.

A similarly organized mechanism may be used to control the angular shift of the swinging frame 54 to move the work holdingframe 50 laterally of the attachment toward one side or th e other depending upon which one of the pair of pawls 32 or 33 is permitted to become effective.

Referring to FIGS. 1 and 2, the mechanism will now be described whereby the pawls may be selectively rendered effective in response to pattern information carried on the punched tape 11.

Each of the pawls 30, 31, 32 and 33 is biased by a light coil spring toward the ratchet wheel with which it cooperates; in FIG. 1 the light wire springs 70 and 71 serve to bias the pawls 30 and 31 respectively. Each of the pawls 30, 31, 32 and 33, moreover, carries an upstanding post 80, 81, 82 and 83 respectively, which slidably abut elongate fingers 90, 91, 92 and 93 respectively extending from levers 100, 101, 102 and 103 respectively. The levers 100, 101, 102 and 103 pivoted on a common pivot stud 104 in the attachment frame and are stabilized on a common guide stud 105 in the attachment frame with each lever being lightly biased by a spring 106 toward the tape carrying drum 41.

Each of the levers 100, 101, 102 and 103 carries a pivoted probe finger 107 of which one is shown on lever 100 in FIG. 1. A light coil spring 108 urges each of the probe fingers 107 into a position substantially perpendicular to the lever on which it is carried and provides for the probe to have capacity for turning movement relatively to the lever. The slots 45 in the sheet metal guide 44 about the tape carrying drum 41 are disposed opposite the probe fingers 107 on each of the levers 100,101,102 and 103.

The punched tape 11 is fonned with four lines of punched holes 110, 111, 112 and 113 spaced to correspond with the spacing of the slots 45. The frequency and orientation of the holes in the four lines of holes punched in the tape determines a pattern of movement of the work holding frame.

A bracket 120 secured on the pawl carrier 37 engages a camming lever 121 fulcrummed on a shoulder screw 122 in the attachment frame and having an upturned arm 123 which engages the levers 100, 101 102 and 103. During each downstroke of the operating lever 23, the camming lever 121 will force all of the levers 100, 101, 102 and 103 away from the drum 41 and the pawl 38 will index the drum by cooperation with the ratchet wheel 40. On each upstroke of the operating lever 23 the camming lever 121 will release all of the levers 100, 101, 102 and 103. Any of these levers of which the probe finger 107 finds a punched hole in the tape 11 will continue to move inwardly and release the corresponding pawl 30, 31, 32 or 33 for engagement with the ratchet wheel with. which it cooperates. The work holding frame 50 will thus be shifted incrementally in directions depending upon the location of holes in the punched tape. The control affected by the punched tape 11 will be incremental in the sense that pattern information will build only from one stitch to the next and not in an absolute sense with respect to any common basis of reference.

It will be appreciatedthat since the patterning system above described is of an incremental type the lines of punched holes in the tapell can dictate an indentiflable pattern of stitches only from a predetermined starting position within the field presented by the aperture 51 of the work holding frame. In order that differently punched tapes 11 may be accommodated each requiring a different starting position, this invention provides a manually influenced means for preselecting the starting position.

FIG. 3 illustrates this manually influenced means as applied to the mechanism for shifting the work holding frame in the direction of the guide slot 53. It will be appreciated that the same type of construction may be used in the mechanism for shifting the work holding frame in the other direction.

A regulating gear is journalled in the attachment frame in mesh with the gear 63 which is fast on the rotary actuator 62. Preferably, the regulating gear 150 is of the same pitch diameter as the gear 63 so as to turn at the same rate as the gear 63. Indicia 152 carried on the regulating gear 150 is visible through an access window 153 in the attachment frame which window 153, may also carry a reference line 154 which in cooperation with the indicia 152 shows the position of the work holding frame in the direction longitudinally of the attachment frame.

A shaft 155 with a knurled handle 156 attached thereto is rotatably and axially shiftable in the attachment frame. The shaft v155 carries a pinion 157 which can be shifted into mesh with the regulating gear 150 for operator influence of the starting position of the work holding frame in a direction longitudinally of the attachment.

Although the mechanism for shifting the work holding frame 50 laterally of the attachment has not been discussed in detail, it may be organized similarly to that shown'in FIG. 3 for the lengthwise direction of movement. A regulating gear 160 is provided for the lateral direction shifting mechanism which functions in the same fashion as the regulating gear 150 for the longitudinal direction shifting mechanism. Preferably, the regulating gears 150 and 160 are arranged coaxially and have gear teeth which are of the same pitch diameter and size. The regulating gear 160 which is beneath the regulating gear 150 may have a cylindrical skirt 161 which is marked with indicia 162 cooperating with a reference line 164 on the access window 153. By moving the shaft 155 axially, the pinion 157 may be placed in mesh selectively with either regulating gear 150 or 160 and the starting position for any selected pattern tape 11 may thus be adjusted. It is preferable that each tape 11 should have imprinted thereon the indicia 152 or 162 corresponding to the necessary starting position for the arrangement of punched holes therein.

With the arrangement of this invention, not only may different tapes be substituted in the attachment, but tapes may be used which begin and end a stitch pattern at different positions within the possible stitching area. Such tapes may be started in either direction if marked as shown in P16. 1, at each end so that the operator can set the proper starting position.

Having set forth the nature of this invention, what is claimed herein is:

1. A work shifting mechanism for use on a sewing machine and including a work holding frame shiftable within a range of positions, shifting mechanism operatively connected to said work holding frame, a drive means for said shifting mechanism, an incremental pattern control system for regulating the operation of said shifting mechanism by said drive means, manually influenced means for operating said shifting mechanism independently of said incremental control system to locate said work holding frame in any selected one of said range of positions.

2. A work shifting mechanism as set forth in claim 1 in which indicia are associated with said manually influenced means for providing visual representation of the position of the work holding frame, in which said incremental pattern control system is responsive to any selected one of a multiplicity of record carrying elements, and in which each of said record carrying elements is marked with specific indicia to which said manually influenced means is required to be set for the production of a predetermined pattern of stitches as a result of machine operation under the influence of said record carrying elements.

3. A work shifting mechanism as set forth in claim 1 in which said shifting mechanism for said work holding frame includes two independently operable shifting mechanisms each effective to influence'the movement of said work holding frame in a different direction, and in which said manually influenced means for operating said shifting mechanism includes two independently operative motion transmitting trains effective each to locate said work holding frame in a selected position in one of said different directions of movement of said work holding frame.

4. A work shifting mechanism as set forth in claim 3 in which said independently operable shifting mechanisms each includes a rotating actuator operatively connected to impart movement in one direction to said work holding frame and having a gear secured to turn with said rotary actuator, and in which said manually influenced means includes a gear accessible to a machine operator and arranged for meshing with said gear secured to said rotary actuator.

5. A work shifting mechanism as set forth in claim 4 in which the gear included in the manually influenced means for each of said independent shifting mechanisms is of the same pitch diameter as the gear secured toturn with the rotary actuator, and in which means is provided for exposing indicia on the gears included in the manually influenced means to the view of an operator.

6. A work shifting mechanism as set forth in claim 5 

1. A work shifting mechanism for use on a sewing machine and including a work holding frame shiftable within a range of positions, shifting mechanism operatively connected to said work holding frame, a drive means for said shifting mechanism, an incremental pattern control system for regulating the operation of said shifting mechanism by said drive means, manually influenced means for operating said shifting mechanism independently of said incremental control system to locate said work holding frame in any selected one of said range of positions.
 2. A work shifting mechanism as set forth in claim 1 in which indicia are associated with said manually influenced means for providing visual representation of the position of the work holding frame, in which said incremental pattern control system is responsive to any selected one of a multiplicity of record carrying elements, and in which each of said record carrying elements is marked with specific indicia to which said manually influenced means is required to be set for the production of a predetermined pattern of stitches as a result of machine operation under the influence of said record carrying elements.
 3. A work shifting mechanism as set forth in claim 1 in which said shifting mechanism for said work holding frame includes two independently operable shifting mechanisms each effective to influence the movement of said work holding frame in a different direction, and in which said manually influenced means for operating said shifting Mechanism includes two independently operative motion transmitting trains effective each to locate said work holding frame in a selected position in one of said different directions of movement of said work holding frame.
 4. A work shifting mechanism as set forth in claim 3 in which said independently operable shifting mechanisms each includes a rotating actuator operatively connected to impart movement in one direction to said work holding frame and having a gear secured to turn with said rotary actuator, and in which said manually influenced means includes a gear accessible to a machine operator and arranged for meshing with said gear secured to said rotary actuator.
 5. A work shifting mechanism as set forth in claim 4 in which the gear included in the manually influenced means for each of said independent shifting mechanisms is of the same pitch diameter as the gear secured to turn with the rotary actuator, and in which means is provided for exposing indicia on the gears included in the manually influenced means to the view of an operator.
 6. A work shifting mechanism as set forth in claim 5 in which said manually influenced means includes a shaft carrying an operating knob and a pinion, and means shiftably supporting said shaft for axial movement to carry said pinion into mesh selectively with the gears of either one of said two independently operable shifting mechanisms. 